Hi, there.
I'm refining a 1.76 A structure. The r-work stuck at 21%, rfree is 24%
after adding waters.
But there is something between the interfaces of the dimers.
The space group is I4122, so it looks like something small, five or
six atoms all together (without hydrogens).
I tried to fit Tris in, however, it didn't look good at all.
The crystal came out from Tris-cl buffer, ammonium sulfate, and there
is some NaCl in the protein buffer too.
The crystals were dropped into 20% xylitol and flash frozen.
Fo-Fc maps are attached at 3 sigma level.
Let me know what you're thoughts are.
Thank you for your help.
Shu
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Shu Xu
Ph.D candidate in Chemistry
Department of Chemistry
The University of Toledo
Toledo, OH 43606
Tel 419-530-1524
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